The purpose of this research center is to provide facilities for the conduct of clinical research at the Tufts-New England Medical Center Hospital. The unit serves the research requirements of the entire medical center and is capable of providing a wide base of support for a variety of clinical studies. The major studies now under way are: epidemiology and biology of medullary carcinoma of the thyroid, adrenocortical and other endocrine functions in glaucoma, effect of hypertransfusion on the short- and long-term outcome of the thalassemia major and sickle cell anemia, control of the secretion of the thyrotropic releasing hormone and other hypothalamic hormones, high dose chemotherapy in osteogenic sarcoma and Ewing's sarcoma, continuous desferrioxamine B infusion in iron overloaded thalassemic patients, investigations of human immune complex diseases, treatment with penicillamine in primary biliary cirrhosis, study of hirsute and virilized females, respiratory physiology in simple obesity (pre- and post-bypass surgery), studies in metabolic neuromuscular disease, nutritional status, health and growth of vegetarian children, diet and colon cancer, bone marrow transplantation, use of DDAVP in the treatment of central diabetes insipidus, mechanisms of hyperprolactinemia, the use of bromoergocryptine in resistant acromegaly, Cushing's disease and secondary amenorrhea, and in medullary carcinoma of the thyroid, study of endocrine function in renal disease with particular reference to the control of growth hormone secretion in renal failure, hypothalamic pituitary function in patients with brain neoplasia, investigation of brittle diabetes and the effect of beta-adrenergic blockage on glucagon release and its role in management of brittle and insulin-dependent diabetes, hypercalciuria, protein sparing fast, anorexia nervosa, in vitro titration of acid-base balance during chronic hypocapnia, the effect of salt loading on salt excretion, effects of somatostatin and carbohydrate, protein and lipid metabolism in diabetes and acromegaly on growth hormone secretion, on insulin requirement in diabetes, and on the pituitary-thyroid axis.